Spinning machine and method of operating the same

ABSTRACT

A spinning machine and a method of operating it. The spinning machine has one or more rotary spinning chambers each of which receives fibrous sliver from a rotary carding and feed roller, spins it into a yarn and has the yarn withdrawn by a withdrawing device. To stop the operation of the machine, the drive of the feed and carding roller is first terminated and simultaneously positive braking action is applied to the roller. Thereupon the withdrawing device has its drive terminated and only then is the rotary spinning chamber disconnected from its own drive.

United States Patent Boucek et a1.

[54] SPINNING MACHINE AND METHOD OF OPERATING THE SAME [72] Inventors: Miroslav Boucek; Miroslav Jiskra, both of Usti Nad Orlici, Czechoslovakia [73] Assignee: Vyzkumny Ustav Bavlnarsky, Usti nad Orlici, Czechoslovakia 221 Filed: .lan.6, 1971 [21] Appl.No.: 104,245

[30] Foreign Application Priority Data Jan. 19, 1970 Czechoslovakia ..36770 [52] US. Cl. ..57/58.95, 57/78, 57/156 [51] Int. Cl. ..D01h1/12 [58] Field of Search.....57/34 R, 58.89, 58.91, 58.93,

[56] References Cited UNITED STATES PATENTS 3,354,626 11/1967 Cizek et a1. ..57/58.89 X

Elias et a1. ..57/58.95 Sterba et a] ..57/78 Primary Examiner-Wemer H. Schroeder AttorneyMichael S. Striker [5 7] ABSTRACT A spinning machine and a method of operating it. The spinning machine has one or more rotary spinning chambers each of which receives fibrous sliver from a rotary carding and feed roller, spins it into a yarn and has the yarn withdrawn by a withdrawing device. To stop the operation of the machine, the drive of the feed and carding roller is first terminated and simultaneously positive braking action is applied to the roller. Thereupon the withdrawing device has its drive terminated and only then is the rotary spinning chamber disconnected from its own. drive.

6 Claims, 1 Drawing Figure PATENTEDHM 17 m2 INVENTOR HIMM Bani! BY "Ill $040 773% I? hr ATTOR N EY SPINNING MACHINE AND METHOD OF OPERATING THE SAME BACKGROUND OF THE INVENTION The present invention relates generally to a spinning machine, and more particularly to a so-called open-end spinning machine. Still more particularly the present invention relates to a method of stopping the operation of such a spinning machine and to an arrangement for l effecting this method.

It is already known to construct so-called open-end spinning machines comprising a plurality of spinning units each of which has a rotary spinning chamber, a feed mechanism and a withdrawing and wind-up mechanism. The feed mechanism is in form of carding roller which separates fibrous sliver into its individual fibers and supplies them to the rotary spinning chamber. The latter rotates at high speed and is provided in its circumferential wall with air-escape apertures through which air can escape due to the centrifugal forces resulting from the high-speed rotation of the chamber, with a consequent underpressure which develops in the chamber and which draws the fibers into the chamber where they are spun into a yarn. The yarn is withdrawn by the withdrawing mechanism and wound by means of the winding mechanism onto a bobbin. The feed mechanism, the withdrawing mechanism and the winding mechanism are mounted on independent shafts.

When a spinning machine of this type is to be stopped, feeding of the fibers by the carding and feeding roller is first stopped. The spinning chamber of each unit continues to rotate until the fibers still within it have been spun into yarn and thereupon the withdrawing roller or rollers with the winding mechanism are stopped. This occurs at the time at which the trailing end of the yarn in the respective unit is still so located as to be under the influence of the under-pressure or suction effect prevailing within the associated spinning chamber. At this time the operation of the spinning chamber is stopped so that the yarn end remains located within the withdrawing tube through which it is withdrawn from the spinning chamber. This is important because when the yarn end is so located in this withdrawing tube that on restarting of rotation of the spinning chamber it is within the range in which the suction effect is capable of acting on the yarn end, the yarn can be brought back onto the collecting surface inside the spinning chamber whereupon feeding of fibers into the spinning chamber is renewed so that new fibers become attached to the trailing end of the yarn and when restarting of the withdrawal of the yarn is initiated, no break will have occurred in the yarn. This is known as priming the spinning chamber.

This approach has, however, the disadvantage that when the feed mechanism is stopped, the combing or carding roller still rotates due to inertia and thus reduces the feeding of fibers into the spinning chamber only gradually, until yarn breakage occurs within the spinning chamber. After a certain time during which the ribbon of fibers on the collecting surface of the rotary spinning chamber has been spun into yarn, it becomes necessary to stop the withdrawing and winding-up mechanisms to let the yarn end remain within the withdrawing tube subject to the suction effect exerted by the spinning chamber. Because of the shortness of time involved, this time sequence is relatively accurately determined, it being understood that the time involved represents a fraction of the time during which the carding roller continues to rotate due to inertia at a decreasing velocity after its drive is switched off. Because the feeding of fibers into the spinning chamber is not terminated immediately, but continues due to the inertial rotation of the carding roller even 0 after the drive of the same has been switched off, the

fibers continue to be supplied to the interior of the spinning chamber at such time at which the withdrawing mechanism for the spun yarn has already been stopped. However, this supply of fibers is not as regular and as even as it is when the machine is in normal operation. The fibers are therefore irregularly distributed on the collecting surface of the spinning chamber which becomes overfilled and as a consequence priming during a subsequent starting-up of the machine is rendered much more difficult. Also, the annulus formed by the fibers on the annular collecting surface of the rotary spinning chamber can become deformed after the rotation of the chamber has been stopped so that a deformed annular ribbon of fibers is present on the collecting surface when the rotation of the spinning chamber is subsequently to be re-started. This, also, makes the priming of the yarn end, that is the reconnection of the trailing yarn end to the newly incoming fibers upon re-starting of the machine, more difficult, particularly if it is to be done automatically in known manner. Of course, at the time at which the machine is restarted and the spinning chamber resumes its rotation, this ribbon becomes still further deformed or becomes collected and bunched up at one point due to the inertial forces acting upon it. The newly fed fibers become deposited on the collecting surface of the spinning chamber and also on the deformed fiber ribbon; when under these circumstances the trailing yarn end is turned into the interior of the spinning chamber by the automatic priming mechanism, it forms with the deformed fiber ribbon a so-called slub, that is a knot which affects both its appearance and its strength. Alternately, the trailing yarn end may not spin into or become connected with such a deformed ribbon and breakage will then occur. In any case, the attendant or operator of the spinning machine must shut down the particular spinning unit and clean the spinning chamber, whereupon priming must subsequently be performed manually, which is a time-consuming process.

It is clear from all of this that to obtain proper stopping of such spinning machines, and consequent proper re-starting of the operation, it is desirable that after the fiber separating and feeding mechanism-that is the carding or combing roller-has its drive switched off, it be positively stopped from continuing to supply fibers to the spinning chamber, and that after the withdrawing and winding mechanisms are also stopped in their operation, no further fibers should be fed into the spinning chamber due to the residual motion of the carding roller or feed roller.

SUMMARY OF THE INVENTION It is, accordingly, an object of the present invention to overcome the aforementioned difficulties.

More particularly it is an object of the present invention to provide an improved method of operating a spinning machine of the type under discussion.

It is a further object of the invention to provide an improved machine of this type.

In pursuance of the above objects, and others which will become apparent hereafter, one feature of the invention resides in a method of stopping a spinning machine having at least one spinning chamber, at least one rotatable feed roller feeding fibers to said spinning chamber for conversion into a yarn, withdrawing means for withdrawing yarn from the spinning chamber, and drives for positively driving the chamber, the roller and the means. This method comprises, briefly stated, the steps of disengaging the feed roller from its associated drive, concomitantly effecting positive braking of the rotation of the feed roller, disengaging the withdrawing-means from the associated drive and finally disengaging the spinning chamber from its drive.

In structural terms, we provide a clutch connecting the feed roller with its drive, which clutch can be disengaged and is provided with a brake for stopping positively the rotation of the feed roller, with both the clutch and the brake being controlled by a control mechanism.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING The single FIGURE is a simplified partially diagrammatic, partially sectioned view of a spinning machine embodying the present invention, with parts omitted for the sake of clarity.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing the drawing in detail it is emphasized that only those portions of a spinning machine are illustrated which are necessary for an understanding of the present invention. The non-illustrated portions are well-known to those skilled in the art and require no detailed explanation or illustration.

As shown, we have chosen to illustrate a spinning machine which comprises a plurality of identical spinning units, of which only three have been shown for purposes of explanation. Each of the spinning units comprises a rotary spinning chamber 1 whose construction per se is already known and which is mounted rotatably about an axis of rotation via bearings 2 journalled in the frame 3 of the machine. A fiber separating mechanism is provided, comprising a carding or combing roller 4 which receives fibrous sliver and separates the same into its constituent fibers. A feeding roller 5 is connected with the roller 4 together with a non-illustrated presser means which is also known, from the US. Pat. No. 3,360,918 (symbol 9). Each of the units further has a withdrawing and winding-up mechanism for yarn, consisting of a pair of withdrawing rollers 6 (one shown of each) and a winding roller 7 against which a bobbin 8 bears to be rotated thereby. A sliver bobbin 9 is provided at the lower part of the respective spinning unit and carries sliver 10 of fibrous material which is to be supplied to the carding roller 4.

As already pointed out, the spinning chambers 1 are standard in their configuration and operation, meaning that they are well-known to those skilled in the art. They have air escape openings on their circumferential wall so that air can escape from them as they rotate at high speed, thereby creating an underpressure with a consequent suction effect which draws fibers into the interior of the respective spinning chamber 1. A pulley 11 is mounted on the shaft of the respective spinning chamber and is driven by a drive belt 12 which extends along the machine and is common to all of the spinning units, being driven by an electric motor 13. The withdrawing rollers 6 and the winding up roller 7 are mounted on shafts l4 and 15, respectively, which are all interconnected by a chain 16 guided over gears 17 and 18 and advanced by them. One of the shafts l4 and 15 is connected to the electric motor 19 by means of a reversing clutch 28 and provided with an electromagnetic brake 33.

A shaft 20 mounts the carding rollers 4 of the various units and is connected with a drive in form of an electric motor 21 via a clutch 22. The opposite end of the shaft 20 is equipped with a brake 23. Feed rollers 5 are mounted on a shaft 24 which is driven by an electric motor 25 with a clutch 26 being interposed between the two, and with the opposite end of the shaft 24 being provided with a brake 27. The clutches 22, 26 and the brakes 23 and 27 are electromagnetically controlled.

A control device 29 (as being known, e.g., from the US. Pat. Nos. 3,354,631 and 3,354,626) is provided with two control elements, namely a starting button 30 and a stop button 31. Such control devices 29 are already well known in the art and require no detailed discussion. It is merely necessary to point out that the device 29 controls in known manner the operation of the various mechanisms of the entire spinning machine in such a manner that in an adjustable time sequence the drives are controlled in a suitable sequential manner. In other words the electric motors 13, 19, 21, and 25, the clutches 22, 26 and 28 and the brakes 23, 33 and 27 are connected with the device 29 by electrical conductors as illustrated.

When the spinning chamber 1 rotates in its bearings 2, air escapes from the interior of the spinning chamber through the outlet openings provided for this purpose due to centrifugal force. The underpressure thus obtained causes an airflow into the chamber which draws the separated fibers from the carding roller 4 through a non-illustrated passage communicating with the roller 4 and the chamber 1. The fibrous sliver 10 is supplied to the carding roller 4 by the feed roller 5 and is separated into its constituent fibers by the roller 4 before it is drawn into the chamber 1. The separated fibers are laid down on the non-illustrated internal collecting surface on the inner wall of the rotary spinning chamber 1 and formed thereon a fiber ribbon which is twisted by the rotary motion of the spinning chamber 1 and thus converted into a yarn 32. The latter is withdrawn by the withdrawing rollers 6 and subsequently wound onto the bobbin 8 by means of the driven winding roller 7.

Thus far, the operation and construction of the respective spinning units of the spinning machine are conventional, except for the provision of the clutches and brakes associated with the carding and feed rollers 4,5.

Correct collective priming of the yarn in all spinning chambers of the various units in the machine, upon start-up of the machine, requires that the individual constituent components of the various units have been previously stopped in an accurate time sequence depending on the yarn number to be spun. When the machine is operating and is to be stopped, the pushbutton 31 of the control device 29 is depressed. This results in an initial disconnecting of the drives for the carding roller 4 and the feed roller 5, in that the electromotors 21 and 25 driving them are switched off. Simultaneously with de-energization of these electromotors the clutches 22 and 26 become disengaged and the brakes 23 and 27 become actuated to brake almost instantaneously the carding roller 4 and the feed roller 5. Thus, the further supply of fibers to the spinning chamber 1 is terminated almost immediately upon de-energization of the drives 21 and 25.

It will be appreciated that instead of mechanical brakes 23 and 27 a dynamic braking of the electromotors 21 and 25 can also be utilized, and equally well such dynamic braking and mechanical braking can be combined if desired. What is important is that the rollers 4, 5 be braked rapidly and effectively so that they do not continue to supply fibers into the interior of the spinning chamber 1 when their drives are de-energized. This assures that after the withdrawing and winding rollers 6 and 7 are subsequently stopped by de-energizing their respective drives, no further separation and feeding of the fibers into the spinning chamber takes place.

Once the drives for the rollers 4 and 5 have been stopped and the brakes therefore activated, the control device 29 de-energizes the drives 19 for the withdrawing and winding rollers 6 and 7 and simultaneously activates the brakes 33 therefor, but with such a delay relative to the actuation of the brakes for the rollers 4 and 5 that the fiber ribbon in the spinning chamber 1 can be converted into a yarn whose trailing end, however, will remain within the withdrawing tube 34 of the associated rotary spinning chamber 1 upon complete stoppage of the rollers 6 and 7, so that when the chamber 1 is restarted, it can be drawn into the interior thereof by the suction effect created thereby.

According to the invention it is advantageous that the brakes 23 and 27-or their equivalents-stop operation of the combing and feeding rollers 4 and 5 in such a manner as to effect their complete standstill within the time interval between de-energization of their drives 21 and 25 and the initiation of the brakes for the rollers 6 and 7. It is during this time period that the fiber ribbon still within the spinning chamber 1 is converted into a yarn 32. Subsequently the drive of the spinning chamber 1 is terminated by switching off the electromotor 13. This is true of course of all of the spinning units although it has been described only with reference to a single one thereof.

lf subsequentlythe spinning machine is to be restarted, this is again effected by the control device 29 by depressing the starting button 30. Once this has been done, the device 29 will first energize the electromotors i3, 19. 21 and 25 whereby the spinning chambers have rotary motion imparted to them. After a time delay so calculated as to permit the motors 13, 19, 21, and 25 to start up and to permit the spinning chambets 1 to start rotating, the device 29 engages clutches 22 and 26 to effect rotational of the carding rollers 4 and feed rollers 5. This renews the feeding of fibers into the spinning chambers 1. Now the reversing clutch 28 is engaged which for a certain predetermined time intervafwill impart reverse motion to the withdrawing and winding rollers 6 and 7 so that the trailing end of the yarn 32 in the respective withdrawing tube is returned into the associated rotary spinning chamber where it contacts the collecting surface and becomes adhered to the fiber ribbon forming thereon. Now the reversing clutch 28 reverses operation of the withdrawing and winding rollers 6 and 7 so that the same now begin to withdraw the yarn again.

At this time yarn 32 is now continuously withdrawn again from the rotary spinning chambers l and wound by the winding roller 7 onto a bobbin 8. If a yarn breakage occasionally takes place during operation of the machine, it is removed manually after the spinning chamber has first been cleaned out. This, however, is not part of the present invention.

Evidently, modifications are possible without departing from the scope and concept of the present invention. Thus, it is for instance possible to mount the carding rollers and/or the withdrawing rollers and the like on various independent shafts and to impart drive to them by a belt extending along the entire machine and driving via suitable pulleys or the like all of these shafts carrying the identical rollers, for instance all the shafts carrying the carding rollers 4 of the various units.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in a spinning machine, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:

1. A method of stopping a spinning machine having at least one spinning chamber, at least one rotatable carding roller having a periphery adapted to receive fibers and to feed them to said spinning chamber for conversion into a yarn, fiber supply means for supply ing fibers onto said periphery of said carding roller, withdrawing means for withdrawing yarn from said spinning chamber, roller and withdrawing means, comprising the steps of disengaging said carding roller from its associated drive; concomitantly effecting positive braking of the rotation of said carding roller so as to prevent the transference of fibers still on its periphery into said spinning chamber; disengaging said withdrawing means from the associated drive; and finally disengaging said spinning chamber from its drive.

2. A method as defined in claim 1, wherein the step of disengaging said withdrawing means is initiated subsequent to the step of braking said roller.

3. A method as defined in claim 2, wherein the step of braking said roller is at least substantially completed before initiation of said step of disengaging said withdrawing means.

4. In a spinning machine, in combination, at least one rotary spinning chamber; at least one rotatable carding roller having a periphery adapted to receive fibers and to transfer them to said spinning chamber for conversion into a yarn; fiber supply means for supplying fibers onto said periphery of said carding roller; withdrawing means .for withdrawing yarn from said spinning chamber; separate drive means for said chamber, said roller and said withdrawing means respectively operatively associated with the same; and terminating means for terminating driving of said chamber, roller and withdrawing means by the respective drive means, said terminating means including a disengageable clutch connecting said carding roller with said drive means therefor, and brake means for positively stopping rotation of said carding roller upon disengaging of said clutch.

5. in a spinning machine as defined in claim 4; further comprising control means for effecting disengagement of said clutch with concomitant operation of said brake means.

6. lnja spinning machine as defined in claim 4; further comprising control means for effecting disengagement of said clutch with concomitant operation of said brake means and subsequent sequential disengagement of said withdrawing means and said spinning chamber from the respectively associated drive means. 

1. A method of stopping a spinning machine having at least one spinning chamber, at least one rotatable carding roller having a periphery adapted to receive fibers and to feed them to said spinning chamber for conversion into a yarn, fiber supply means for supplying fibers onto said periphery of said carding roller, withdrawing means for withdrawing yarn from said spinning chamber, roller and withdrawing means, comprising the steps of disengaging said carding roller from its associated drive; concomitantly effecting positive braking of the rotation of said carding roller so as to prevent the transference of fibers still on its periphery into said spinning chamber; disengaging said withdrawing means from the associated drive; and finally disengaging said spinning chamber from its drive.
 2. A method as defined in claim 1, wherein the step of disengaging said withdrawing means is initiated subsequent to the step of braking said roller.
 3. A method as defined in claim 2, wherein the step of braking said roller is at least substantially completed before initiation of said step of disengaging said withdrawing means.
 4. In a spinning machine, in combination, at least one rotary spinning chamber; at least one rotatable carding roller having a periphery adapted to receive fibers and to transfer them to said spinning chamber for conversion into a yarn; fiber supply means for supplying fibers onto said periphery of said carding roller; withdrawing means for withdrawing yarn from said spinning chamber; separate drive means for said chamber, said roller and said withdrawing means respectively operatively associated with the same; and terminating means for terminating driving of said chamber, roller and withdrawing means by the respective drive means, said terminating means including a disengageable clutch connecting said carding roller with said drive means therefor, and brake means for positively stopping rotation of said carding roller upon disengaging of said clutch.
 5. In a spinning machine as defined in claim 4; further comprising control means for effecting disengagement of said clutch with concomitant operation of said brake means.
 6. In a spinning machine as defined in claim 4; further comprising control means for effecting disengagement of said clutch with concomitant operation of said brake means and subsequent sequential disengagement of said withdrawing means and said spinning chamber from the respectively associated drive means. 